Hartz is a surname, and may refer to:

• Donna Hartz, Aboriginal Australian midwife and academic
• Glenn A. Hartz, American philosopher
• Harris Hartz (born 1947), U.S. federal judge
• Harry Hartz (1896—1974), U.S. racecar driver
• Jim Hartz (1940–2022), U.S. television personality
• Louis Hartz (1919—1986), U.S. political scientist
• Nikolaj Hartz (1867—1937), Danish geologist and botanist
• Peter Hartz (born 1941), German business executive (Hartz concept)
• William J. Hartz, U.S. composer and lyricist

The corporate name may refer to:

• Hartz Mountain Industries, a real estate and pet product conglomerate

• Hartz Mountains (Tasmania)
• Harz Mountains (Germany)